The present invention relates to an electronic camera having a plurality of photographing and recording modes.
Recently, there has been developed an electronic still camera having an optical system in which the optical image of an object is formed on an image pickup element, an exposure control system in which an amount of exposure corresponding to the luminance of the object is set for the image pickup element, and a recording system in which the output signal of the image pickup element is recorded as a field or frame of a still picture on a magnetic disk. The electronic still camera is advantageous in that the exposure time can be freely selected; however, it is nevertheless disadvantageous in the following points: The recording medium is a magnetic disk on which signals are recorded concentrically. Therefore, the electronic still camera is not suitable for photographing motion pictures. In the case of an electronic still camera having an optical viewfinder, the state of the object cannot be confirmed if the eye is moved from the viewfinder. Therefore, the camera is not suitable for the case where it is required for a person remote from the camera to perform the photographing operation. In addition, it is impossible for a plurality of persons to simultaneously observe the object through the viewfinder.
On the other hand, it is well known in the art that, in a conventional video camera and VTR system, the output signals of the image pickup element are recorded as motion pictures on a magnetic tape, and the image of the object can be confirmed through a monitor at all times. In the video camera as in the electronic still camera described above, an image pickup signal is obtained from an image pickup element. Therefore, if the electronic still camera is deisgned so as to be able to operate in a video camera mode, then it can be expected that the above-described difficulties accompanying the electronic still camera will be eliminated and the types of applications for the electronic still camera expanded.
In the case where the video camera mode is provided for the electronic still camera, the image of an object can be confirmed with a monitor. Therefore, a system taking a middle position between those of the electronic still camera and the video camera can be considered in which one field (corresponding to an exposure time of 1/60 second) or one frame (corresponding to an exposure time of 1/30 second) of a still picture is recorded on a magnetic disk (hereinafter referred to as "a one-shot video camera system" when applicable).